metal ceramic crowns pp- 142- 151. metal-ceramic restoration also called porcelain fused to metal...
TRANSCRIPT
METAL-CERAMIC RESTORATION
ALSO CALLED PORCELAIN FUSED TO METAL RESTORATION (PFM).
CONSIST OF A CERAMIC LAYER BONDED TO A THIN CAST METAL COPING THAT FITS OVER THE TOOTH PREPARATION.
METAL CERAMIC RESTORATION
COMBINES THE
STRENGTH AND
ACCURATE FIT OF A
CAST RESTORATION
WITH THE COSMETIC
EFFECT OF A
CERAMIC CROWN.
METAL-CERMIC RESTORATION
WITH THE METAL UNDERSTRUCTURE,METAL-CERAMIC RESTORATIONS HAVE GREATER STRENGTH THAN RESTORATIONS MADE OF CERAMIC ALONE.
METAL-CERMIC RESTORATION
CAN BE USED IN A
WIDE VARIETY OF
SITUATIONS
INCLUDING THE
REPLACEMENT OF
MISSING TEETH
WITH FPD’S.
METAL-CERMIC RESTORATION
IS A COMBINATION OF METAL AND CERAMIC, THE TOOTHPREPARATION IS ALSO COMBINATION OF DEEPREDUCTION FACIALLY AND SHALLOWER REDUCTION LINGUALLY.THERE MAY BE A WING ON EACH PROXIMAL SURFACE WHERE THE DEEP REDUCTION ENDS AND THE SHALLOWER PROXIMALREDUCTION BEGINS.
METAL-CERMIC RESTORATION
Inadequate space for a
sufficient thickness of
ceramic material-
1. Poorly contoured restoration affecting both esthetic and health of the surrounding gingiva.
METAL-CERMIC RESTORATION
2.The shade and translucency of the restoration will not match the adjacent natural teeth.
ANTERIOR METAL-CERAMIC CROWNS
A UNIFORM
REDUCTION OF
APPROXIMATELY
1.2MM IS NEEDED
OVER THE ENTIRE
FACIAL SURFACE.
ANTERIOR METAL-CERAMIC CROWNS
TO ACHIEVE ADEQUATE REDUCTION WITHOUT ENCROACHING UPON THE PULP – FACIAL SURFACE PREPARED IN TWO PLANES THAT CORRESPOND ROUGHLY TO THE TWO GEOMETRIC PLANES PRESENT ON THE FACIALSURFACE OF AN UNCUT TOOTH
ANTERIOR METAL-CERAMIC CROWNS
FACIAL SURFACE IS PREPARED IN A SINGLE PLANE THAT IS AN EXTENSION OF THE GINGIVAL PLANE – INCISAL EDGE WILL PROTRUDE RESULTING IN BAD SHADE MATCH OR OVERCONTOURED “BLOCK”.
ANTERIOR METAL-CERAMIC CROWNS
FACIAL SURFACE
PREPARED IN ONE
PLANE THAT HAS
ADEQUATE FACIAL
REDUCTION IN THE
INCISAL ASPECT- FACIAL
SURFACE OVERTAPERED
AND TOO CLOSE TO THE
PULP.
ARMAMENTARIUM
1. LAB KNIFE WITH NO:25 BLADE
2. SILICONE PUTTY3. ROUND – END TAPERED
DIAMOND4. SMALL WHEEL DAIMOND5. LONG NEEDLE DAIMOND6. RADIAL FISSURE BUR
(ROUNDED SHOULDER)7. MODIFIED BINANGLE
CHISEL
ANTERIOR METAL-CERAMIC CROWNS
SILICONE INDEX
MADE BEFORE
TOOTH
PREPARATION
TOOTH BADLY
BROKEN DOWN,
INDEX MADE ON WAXED
UP DIAGNOSTIC CAST.
ANTERIOR METAL-CERAMIC CROWN PREPARATION
STEP NO : 1PLACEMENT OF DEPTH ORIENTATION GROOVES - ( 1.2MM )THE LABIAL GROOVES CUT IN TWO SETS1. ONE SET PARALLEL
WITH THE GINGIVAL HALF OF LABIAL SURFACE
2. ONE SET PARALLEL WITH THE INCISAL HALF OF LABIAL SURFACE
ANTERIOR METAL-CERAMIC CROWN PREPARATION
STEP NO : 2
INCISAL REDUCTION-
(2MM)
ROUND –END
TAPERED DAIMOND.
ANTERIOR METAL-CERAMIC CROWN PREPARATION
Inadequate incisal reduction results in poor incisal translucency
ANTERIOR METAL-CERAMIC CROWN PREPARATION
STEP NO : 3
LABIAL REDUCTION
(INCISAL HALF)
ROUND- END
TAPERED DAIMOND.
ANTERIOR METAL-CERAMIC CROWN PREPARATION
STEP NO :4
LABIAL REDUCTION
(GINGIVAL HALF)
ROUND-END
TAPERED DAIMOND
ANTERIOR METAL-CERAMIC CROWN PREPARATION
STEP NO : 5
LINGUAL REDUCTION
(0.7 -1MM )
SMALL WHEEL
DAIMOND.
ANTERIOR METAL-CERAMIC CROWN PREPARATION
STEP NO : 7
LINGUAL AXIAL
REDUCTION
ROUND - END
TAPERED DAIMOND.
ANTERIOR METAL-CERAMIC CROWN PREPARATION
FACIAL MARGIN
1. DEEP CHAMFER
2. SHOULDER WITH BEVEL
3. SHOULDER
4. RADIAL SHOULDER
ANTERIOR METAL-CERAMIC CROWN PREPARATION
DEEP (HEAVY ) CHAMFER
PROVIDE 90-DEGREE
CAVOSURFACE ANGLE
WITH A LARGE –RADIUS
ROUNDED INTERNAL
ANGLE.
ANTERIOR METAL-CERAMIC CROWN PREPARATION
RADIAL SHOULDER
MODIFIED FORM OF
SHOULDER
SMALL RADIUS
INTERNAL ANGLE
WITH 90-DEGREE
CAVOSURFACE
ANTERIOR METAL-CERAMIC CROWN PREPARATION
SHOULDER WITH BEVEL
THIS DESIGN CAN BE
USED- GINGIVAL
ESTHETICS ARE NOT
CRICTICAL
ANTERIOR METAL-CERAMIC CROWN PREPARATION
IMPROVED ESTHETICS
ALL CERAMIC LABIAL
MARGIN
THIS ELIMINATES THE
METAL COLLAR AT THE
FACIOGINGIVAL MARGIN
OF THE FINISHED METAL-
CERAMIC RESTORATION
ANTERIOR METAL-CERAMIC CROWN PREPARATION
IMPROVED ESTHETICS
ALL CERAMIC LABIAL
MARGIN
THIS ELIMINATES THE
METAL COLLAR AT THE
FACIOGINGIVAL MARGIN
OF THE FINISHED METAL-
CERAMIC RESTORATION